Method of treating metalliferous materials.



"onrr CAR-L FRIEDRICH SIEGEBT, OF JEPPES, NEAR JOHANNESBURG, TRANSVAAL.

METHOD OF TREATING METALLIFEROUS MATERIALS.

No Drawing.

T 0 alt whom it may concern:

Be it known that I, CARL FRIEDRICH SIE- cnnr, a subject of the King ofGreat Britain, and resident of Jeppes, near Johannesburg, Transvaal,have invented certain new and useful Improvements in Methods of TreatingMetalliferous Materials, of which the following is a specification.

This invention relates to a process primarily intended for the treatmentof auriferous black sand, concentrates and the like, although it may beadopted for the treatment of other refractory metalliferous materials orore for recovering the metal contents thereof.

By the use of my process or mode of treatment a very high extraction ofthe metal contents of the ore or material is obtained, and the processis inexpensive and simple and consequently readily carried out.

In treating auriferous ores containing copper the copper is dissolvedduring the treatment and a purer bullion is obtained.

The invention consists in roasting the re fractory ore or heating it toa dull red heat in which condition it is brought into contact with asolution consisting of Water, sodium chlorid and sal-ammoniac. Thesolution is then evaporated by the application of heat to the mass, andsulfuric acid is then added to the now comparatively dry mass. WVater issubsequently added and the mass then mixed. The diluted acid solution isthen allowed to remain in contact with the ore for a suitable length oftime. The solution is thereafter drawn off and water then preferablyadded to the ore mass to wash out the sulfuric acid. This treatmentrenders the metal contents of the ore free so that they can be recoveredby amalgamation in any ordinary or suitable manner.

In carrying out the invention the refractor-y ore is roasted or heatedto a dull red heat in a furnace of any suitable construction or in anyother convenient manner. In treating black sands they may be stirred oragitated either continuously or intermittently during the process ofroasting or heating so as to insure uniform heating of the mass. Intreatingconcentrates or similar refractory metalliferous materials theyare preferably stirred or agitated continuously while being heated toinsure uniform distribution of the heat throughout the mass. Theintermittent or continuous agitation or stirring of the ore or materialmay be effected Specification of Letters Patent.

Patented Jan. 17, 1911.

Application filed July 6, 1909. Serial No. 506,162.

by any suitable means. The roasting or heating of the ore or material iscarried out in such a way that the fumes can readily escape. After allthe fumes have been dispelled the ore or material while still at a dullred heat is placed in or otherwise brought into contact with thesolution consisting of water, sodium chlorid and salammoniac, in orderto free the gold from the oxids. The solution may be conveniently placedin a tank and the ore or material be raked or removed from the roasteror furnace directly into the solution in said tank. The introduction ofthe heated ore or material into the solution is an extremely importantstep in the process of treatment. Suflicient of the solution is used tocover the ore. After introducing the ore into the solution the mass isthen stirred or agitated by any suitable means so as to insure intimatecontact of the solution with all pieces or particles of the ore charge.After the solution has been thoroughly mixed with the ore mass heat isapplied in any convenient maner to the mass to dry it by evaporating thesolution. The ore mass is now treated with the sulfuric acid say bypouring the latter onto the top of the ore preferably in such a manneras to evenly distribute it over the whole surface. "Water is then pouredover the mass and the latter then thoroughly mixed with the diluted acidsolution, After being thoroughly mixed the ore mass and solution areallowed to stand or remain in contact for say twelve hours more or lessaccording to the nature of the ore under treatment.

After the diluted acid solution has remained in contact with the massfor a sufficient length-of time. the solution is then drawn OE and wateris then preferably added to the oremass to wash out the acid solutionwhich might otherwise interfere with the recovery of the metal contentsby amalgamation. When the washing out of the acid solution has beencompleted the ore mass may then be passed over the amalgamating platesto recover the now free metal contents thereof. To admit of this, watermay be mixed with the ore mass to serve as a vehicle or medium forcarrying it over the surfaces of the amalgamating plates.

The sulfuric acid can be reused by adding to it sufficient freshsulfuric acid to bring it up to the requisite strength.

For each ton of ore to be treated I employ say forty two gallons ofwater to which is added ten pounds of sodium chlorid (preferably coarsepan salt) and two gallons of strong sal-ammoniac solution; thesal-ammoniac solution being prepared by dissolving two and a half tothree pounds of salammoniac in one hundred gallons of water.

One pound of sulfuric acid (more or less) is used in treating one ton ofthe ore or material, and say two gallons of water are poured on top ofthe ore mass after the sulfuric acid has been poured over it.

What I claim as my invention and desire to protect by Letters Patent isl. The process for treating metalliferous material which consists inheating the material to a dull red heat, then bringing the heated massinto contact with a solution consisting of-water, sodium chlorid andsalammoniac, then drying the mass by the application of heat, thenadding sulfuric acid to the mass, then drawing oft the acid solution andfinally recovering the now free metal contents of the mass, asset'forth.

2. The process for treating metalliferous material which consists inheating the material to a dull red heat, then bringing the heated massinto contact with a solution consisting of water, sodium chlorid andsalammoniac, then evaporating the water of the solution by theapplication of heat to the mass, then adding diluted sulfuric acid tothe mass, then drawing off the diluted acid solution and finallyrecovering the now free metals of the mass, as set forth.

3. The process for treating metalliferous material which consists inheating the material to a dull red heat, then bringing the heated massinto contact with a solution consisting of water, sodum chlorid andsalammoniac, then evaporating the solution by the application of heat tothe mass, then adding sulfuric acid to the mass, then adding water tothe mass, then drawing off the diluted acid solution and then recoveringthe now free metal contents of the mass, as set forth.

4. The process for treating metalliferous material which consists inheating the material at a dull red heat, then inmmersing the heated massin a solution consisting of water, sodium chlorid and sal-ammoniac, thenapplying heat to the mass to dry it or evaporate the solution, thenadding sulfuric acid to the comparatively dry mass, then adding water tothe mass, then allowing the diluted acid solution to remain in contactwith the ore mass for a suitable length of time, then drawing off thediluted acid solution, then adding water to wash out the sulfuric acidand finally. recovering the now free metal contents of the mass, as setforth.

5. The process for treating metalliferous material which consists inheating the material at a dull red heat in such a way that the fumes canreadily escape, stirring or agitating the material either continuouslyor intermittently during the process of heating to insure uniformheating of the mass, then immersing the material after all the fumeshave been dispelled and while it is still at a dull red heat in asolution consisting of water, sodium chlorid and salammoniac, stirringor agitating the mass to insure intimate contact of the solution withthe material, then applying heat to the mass to dry it or evaporate thesolution, then placing sulfuric acid on the top of the comparatively drymass in such a manner as to evenly distribute the acid over the wholesurface of the mass, then pouring water over the mass, then mixing themass with the diluted acid solution, then allowing the mass and dilutedsulfuric acid solution to remain in contact for a sufficient length oftime, then drawing off the diluted acid solution, then adding water tothe mass to wash outthe acid solution, and then passing the ore massover amalgamating plates to recover the now free metal contents of saidmass, as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

CARL FRIEDRICH SIEGERT.

Witnesses:

CHARLES OVENDALE, FREDERICK An'rI-IUR OVENDALE.

